A random access channel (RACH for short) uses an open-loop power control manner for a power setting. When receiving a random access preamble sent by UE by using the RACH, a base station may use a beamforming technology. In addition, the base station may use different receive beams to receive one or more preambles sent by a user.
Because different receive beams are corresponding to different beamforming gains, the different receive beams may be corresponding to different target receive powers of the base station and different preamble formats used by the user. When the UE sends the preamble, the base station may perform adaptive switching on the receive beams based on quality of receiving the preamble, for example, the base station is switched from a receive beam 1 to a receive beam 2. For example, when reciprocity of a transmit beam and the receive beam of the base station does not exist, when receiving the preamble sent by the UE, the base station needs to poll a plurality of candidate receive beams, to select an optimal receive beam to receive the preamble. In this case, the different receive beams may be corresponding to different power control parameters of the preamble.
However, an existing RACH power control mechanism is usually based on fixed omnidirectional antenna transmission or fixed receive beam transmission. For a scenario in which a receive beam rapidly changes, if the existing power control mechanism is still used, power control of the RACH is not precise enough, thereby affecting an access success rate of an uplink RACH.